It is increasingly the case that cars and other vehicles with combustion engines employ digital rather than conventional analog ignition systems. A digital ignition system is preferable to an analog ignition system since a digital ignition system is generally not affected by temperature and humidity and, thus, provides more accurate and consistent engine performance. However, digital ignition systems heretofore, while accurate, have been of limited flexibility in terms of programmability and robustness. Such digital ignition systems have not allowed the user to take full advantage of a given engine's specific characteristics. Such digital ignition systems have not allowed the user to remotely program ignition parameters in a substantially real-time manner to optimize performance for the circumstances. These are significant disadvantages.
Additionally, each engine may have its own slightly different characteristics in terms of dimensions, composition, weight, flow characteristics, and so on. In layman's terms, each manufactured engine has its own idiosyncrasies. Existing digital ignition systems have not permitted the user to truly optimize performance because certain such idiosyncrasies are not accounted for. In a highly competitive environment, such as racing, this is a significant disadvantage because small improvements in performance can mean the difference in winning a race.
In high performance combustion engine applications, such as drag racing, a capacitive discharge ignition system is often preferred because a capacitive discharge ignition system is fast and efficient at providing energy for creating sparks, especially at high speeds. A capacitive discharge ignition system uses a storage, or "bathtub," capacitor to hold energy until the correct time to make the spark. The capacitor is connected to an ignition coil of the engine through a switch such that, to generate a spark, the switch is activated to dump the charge from the capacitor to a primary side of the ignition coil in less than 1/10.sup.th of a millionth of a second. The voltage applied to the ignition coil as a result of the capacitor discharge is then stepped up by the turns ratio of the ignition coil and applied to spark plugs of the engine for igniting fuel within combustion chambers of the engine.
A significant benefit of this approach is that the capacitor can be charged extremely fast and can hold energy for extended periods with almost no loss or leakage. It can then can release the energy to the ignition coil very quickly. Thus, a capacitive discharge ignition system provides an extremely fast and efficient method of storing and distributing energy to create sparks in an engine, with little or no drop-off in engine performance at high speeds.
However, as is often the case in engineering tradeoffs, there are disadvantages that flow from the use of capacitive discharge ignition systems. For example, the quicker, hotter sparks of a capacitive discharge ignition system results in a shorter duration for each spark, which can disrupt engine performance at low speeds. At high engine speeds, a shorter duration spark is not a problem since the spark is supposed to occur very quickly. But at low engine speeds, the shorter duration sparks can result in poor performance because cylinder pressures and temperatures are low and air/fuel mixtures can be less than optimal. This is a significant disadvantage. There are other challenges presented to the use of a digital ignition system using a capacitive discharge mechanism.
A capacitive discharge engine will preferably also include an engine speed, or "rev limiter" feature to protect the engine from dangerous high speeds, or "over-revving," where the engine could be damaged or even explode. A rev limiter feature turns off the spark to individual cylinders of the engine when engine speed exceeds a preset maximum level. Thus, the engine is purposely caused to misfire so that the engine speed is brought back down to the preset maximum level. Existing implementations of rev limiters have not provided optimum flexibility and programmability to allow the user to readily optimize rev limiting to circumstances. This is a significant drawback.
Another difficulty often encountered in high-performance applications, such as racing, is the tendency of the user to provide too much torque to the wheels upon launch. Often the wheels lose traction and precious time is lost as a result. This can be the difference between winning and losing a race. This is a significant drawback.
Other problems and drawbacks also exist.